1. Field of the Invention
The present invention relates generally Ethernet systems and, more particularly, to a system and method for using sequence ordered sets for energy efficient Ethernet communication.
2. Introduction
Energy costs continue to escalate in a trend that has accelerated in recent years. Such being the case, various industries have become increasingly sensitive to the impact of those rising costs. One area that has drawn increasing scrutiny is the IT infrastructure. Many companies are now looking at their IT systems' power usage to determine whether the energy costs can be reduced. For this reason, an industry focus on energy efficient networks has arisen to address the rising costs of IT equipment usage as a whole (i.e., PCs, displays, printers, servers, network equipment, etc.).
Most network links are typically in an idle state between sporadic bursts of data. In this scenario, the overall link utilization can therefore be relatively low. In other network links, there can be regular or intermittent low bandwidth traffic, with bursts of high bandwidth traffic. In general, reducing link rates when the high data capacity is not needed can save energy. In other words, a link can use a high data rate when data transmission needs are high, and use a low data rate when data transmission needs are low. In designing an energy efficient solution, however, an additional consideration is the extent to which the traffic is sensitive to buffering and latency. For example, some traffic patterns (e.g., HPC cluster or high-end 24-hr data center) are very sensitive to latency such that buffering would be problematic. For these and other reasons, applying energy efficient concepts to different traffic profiles would lead to different solutions. These varied solutions can therefore seek to adapt the link, link rate, and layers above the link to an optimal solution based on various energy costs and impact on traffic, which itself is dependent on the application. One of the significant energy factors is the energy that it takes to get in and out of those states (PHY and above). What is needed therefore is an efficient mechanism for exchanging energy efficient information that can be used in implementing an optimal solution.